Presser-foot-lifting mechanism for sewing-machines.



N0. 708,940. Ptented Sept. 9, I902.

C. TI'IEUBALD.

PBESSEB FOOT LIFTING MECHANISM FOR SEWING MACHINES.

(Application filed Am. 28, 1902.)

(N0 Model.)

2 Sheets-Sheet l.

62/272962? 77e0Za/qi wihieape o v Patented Sept. 9, I902; C. THEUBALD.PRESSER FO'OT LIFTING MECHANISM FOR SEWING MACHINES. I (Applicationfiled Apr. 28, 1902.i (No'ModeL) 2Sheets-Sheet 2.

anwzntoz a'ito'anow wihwaoao' THE NORRIS PETERS 00.. puofoufllouWASNINDTON. u, c.

NrrED STATES "tries.

ATENT CONRAD THEOBALD, OF BRUNING, NEBRASKA.

SPECIFICATION forming part of Letters Patent No. 708,940, datedSeptember 9, 1902.

Application filed April 28, 1902. Serial No. 105,081. (No model.)

To all whom it may concern:

Be it known that I, CONRAD THEOBALD, a citizen of the United States,residing at Bruning, in the county of 'lhayer and State of Nebraska,have invented new and useful Improvements in Sewing-Machines, of whichthe following is a specification.

My invention relates to improvements in sewing-machines, andparticularly relates to lifters for presser-bars and means for holdingthe bar elevated and combined therewith mechanism for adjusting oroperating the tension device; and the objects are to provide improvedmechanism for lifting and holding the presser-bar in raised position bya system of levers arranged to be actuated by the pressure of the kneeor leg of the operator, and at the same time by the same mechanismrelease and apply the tension of the thread as fed from the spool, andalso to provide improved means for engaging the presser-foot bar andhold it in elevated position.

With these objects in View my invention consists in the novelconstruction of parts and their arrangement and aggroupment in Operativecombination, as will be hereinafter fully described and the noveltythereof particularly pointed out and distinctly claimed.

I have fully and clearly illustrated the improvements in theaccompanying drawings, wherein- Figure 1 is a perspective view of asewingmachine having my improvements connected thereto, the table beingbroken away to show the parts of the mechanism located thereun-- der.Fig. 2 is a side elevation of the armof the sewing-machine, partly invertical section, to show the mechanism assembled within the head of thearm. Fig. 3 is a top plan View of the head and portion of the arm,partly in horizontal section, and showing the ratchet-pinion andactuating-pawl arm of the pitman to operate the ratchet. Fig. 4 is adetail front view of the head, showing the presser-bar and attached rackplate or bar. Fig. 5 is a detail perspective of the rack-bar as removedfrom its connectionsto the presserbar. Fig... 6 is a detail perspectiveof the bell-crank lever, showing the teeth to engage the rack-bar of theresser-bar. Fig. 7 is a detail perspective of the ratchet-pinion andtrip-wheel for holding the presser-bar in raised position. Fig. 8 is adetail perspective of the lever which engages the tension devices. Fig.9 is a detail View of the coupling, the parts being shown as separated.Fig. 10 is a perspective view of the tension device, showing the partsas closed. Fig. 11 is a perspective view of the tension device, showingthe upper plate as raised to relieve the tension on the thread.

Referring to the drawings, A designates the standard, and B theoverhanging arms, of the sewing-machine, which may be of any of thewell-known constructions, and O designates the base-plate, on which thestandard is secured or forms an integral part.

It is not deemed essential to describe or show the various actuatingmechanism common to all machines to operate the needle, since these arewell known, and my invention forms no part thereof, being intimatelyassociated with the presser-bar and tension devices.

D designates the head, formed on the free end of the arm and chamberedout to receive the eccentric (not shown) which actuates the needle-bar 1in the usual well-known manner. To the face of the head is secured byany Well-known means the plate 2,. which closes in the mechanism. Thecommon form of presser-bar 3 is carried by the plate 2, being arrangedin a half-circle vertical groove 4: and slidingly projected through aguidebracket 5 and through the flange 6 at the lower end of the plate 1,as shown in the drawings, and on the presser-bar is arranged the usualexpansive spring 7 to return and hold the bar to its lower position whenthe restraint on the spring is removed. My improvements do not interferewith the usual means for lifting and holding the presser-bar in raisedposition, which means consists of a pin 8, projected from the barthrough a slot in the plate, and a cam disk or plate 9, pivotallysupported on the plate 2 and bearing against the pin 8. My improvementsare more particularly utilized when the operator is engaged in doingwork where it is necessary or more convenient to use both hands in itsmanipulation. It does not, however, in-

terfere with the use of the lifting and holding means above described.

Now describing my improvements as illustrated in the drawings, 10designates a lever pivotally mounted under the table, as at 11, and atits free end has jointed to it a legpiece 11, having avertically-depending arm against which the knee or leg of the operatormay engage to operate the lever, the hinged connection of the sectionsor parts of the lever being such that the leg-section turns only toalinement with the lever, as indicated, and so that when not in use itmay be swung around under the table and lie against the lever. The lever10 is slidingly supported on a rigid rod 12, and between the lever andthe wall of the table on the rod 12 is placed an expansive spring 13, bythe force of which when the lever is moved to compress the spring it isreturned to initial position on release of the compressing force. Atabout midway the length of the lever 10 is pivotally connected one endof a rod 14, loosely projected through a hanger 15, depending from thetable. The other and free end of the rod 14 is formed with a hookedcoupling-head 15, which detachably engages with a counterpart coupling16 on the end of a rod 17, loosely supported in a hanger 18, dependingfrom the bottom side or" the base of the sewing-machine, the other andouterend of the rod 17 being pivotally connected to the lower end of arocking lever or rod 19, pivotally supported by a pin 20, fixed in thestandard A. To the upper end of the rock-lever is pivotally secured ahorizontally-arranged pitman 21, to the forward end portion of which,adjacent to the headpiece, is pivotally hung a link or bar 22,constituting a lever, the lower end of which is pivotally arranged on apin 23, fixed in a block or support 24. To the inner projecting end ofthe pin 23 is mounted, to rock thereon, a bell-crank lever 25, havingformed on the end of its lower and forwardly-projecting arm a determinednumber of teeth 26, which engage with a rack carried by the presser-bar.The vertical arm of the bellcrank lever is provided with alaterally-projecting pin 27, which engages in a notch or recess 28 inthe lever 22, so that when the lever-is drawn back by the pitman 21 therecess engages the pin and rocks the bell-crank lever.Tothepresser-barissecured orformed integral therewith a plate 29, formedwith a recess 30 to set over the bracket 5 on the head-plate to permitthe raising and lowering of the presser-bar, and on the inner edge ofthe plate 29 is formed a rack 31, which is engaged by the teeth on theend of the bellcrank lever. The plate 29 is also formed with anelongated recess 32 to afford room for the engagement of the trip wheelor spider to hold the presser-bar in elevated position. In the innerwall of the head is formed a chamber or housing 33, wherein isjournaleda vertical shaft or arbor 34, on which is mounted a ratchetpinion 35,having a determined number of ratchet teeth thereon, usually eight, andabove the ratchet-pinion on the shaft 34 is fixed a trip-spider 36,having four diametrically-disposed arms arranged to project beyond theperimeter of the ratchet-pin ion and into the recess 32 of the plate 29,carried by the presser-bar, so that when the bar is lifted and an arm ofthe spider is turned to engage in the recess the arm will rest under theupper wall of the recess 32 and hold the presser-bar from furtherdescent until the arm of the spider is moved from under the end of therecess, when the presser-bar drops under the force of the spring. Toactuate the ratchet-pinion and spider, the pitman 21 is extended beyondthe connection to the link 22, as at 37, the extension being arranged ina sleeve or way 38, which opens into the chamber 33, wherein theratchet-pinion and spider are contained, and on the end of the extensionis provided or formed a pawl-catch 39, which moves in the path of theratchets and by its engagement therewith turns the pinion to carry thespider-arms into the recess of the plate on the presser-bar and underthe end thereof to hold the presser-bar lifted and at the next movementturns the spider-arm from its engagement and so that the plate of thepresser-bar stands free between two arms of the spider.

It will be perceived from the foregoing description and reference to thedrawings in connection therewith that the operation of the describedmechanism may be stated as follows: The hinged leg-piece is first turnedin alinement with the main bar of lever 10, so as to be accessible tothe knee or leg of the operator, and the coupling having been hooked upthe mechanism is ready for being utilized. Then by pressing the lever 10toward the adjacent end of the table the bars 14 17 are moved in thesame direction, rocking the lever 19 to move its upper end outward,which pulls the pitman in same direction, and with the pitman moves thelever 22 into contact with the pin 27 in the bell-crank lever andraising the lower arm of that lever, which, being in engagement with therack, raises the presser-bar, and when the upper end of the recess 32has passed the spider the pawl-catch on the extension of the pitmanengages the ratchet-pinion and turns it so as to bring an arm of thespider into the recess in the plate of the presser-bar when the pressureon the lever is removed, and the force of the spring 13 throws thelever, with the pitman, in opposite direction and the presserbar is freeto move down and lodge on the arm of the spider in its path. Of coursethe presser-foot is raised by these movements from off the work, and theoperator has both hands free to adjust the work as may be desired orrequired. When it is necessary to release the presser-bar, the mechanismis again brought into requisition and the presser bar lifted or raisedoff its contact with the arm of the spider, which is then turned by thepawl catch and ratchet from under the end of the recess and until theplate on the presser-foot will stand in the angle between two of thearms of the spider and the presserhat-free to descend, when the pressureon the leg-piece can be removed and the mechanism disengaged, in whichposition the connection between the teeth of the bell-crank lever andthe rack on the presser-bar imposes no interference with the freemovement of the bar.

I also provide a tension device operated by the mechanism which liftsthe presser-bar and which relieves the tension on the threadsimultaneously with the operation of the raising of the presser-bar andrestores the tension when the presser-bar is lowered to resume sewing.This tension device is shown in Figs. 1 and 2 in connection with thepitman and illustrated with particularity in Figs. 10 and 11, andreference being thereto had it will be disclosed that on vertical studsformed on the upper side of the arm 13 is arranged a flat metal plate40, formed with a recess or indentation 41 to afford space formanipulating the thread and its insertionin the tension. cured acoincident spring-plate 42, secured by a screw 43, let through bothplates and projecting into one of the studs, substantially as shown. Inthe plate 42 is a thread-slit 44, leading into a thread hole or eye 45,and the end of this plate is formed with a hollow angular sleeve 46. Thethread is yieldingly held between the surfaces of the plates under thespring portion and is fed up through the eye 45 to the usual eyes on thehead of the arms to the needle. To the side of the overhanging arm B issecured a standard 47, provided with a bearing wherein is journaled arod 48, having a vertically-depending arm 49, which loosely engages in aslot formed in aplate 50, secured to the pitman 21. On the free end ofthe rod 48 is aplate5l,which is arranged within the angular sleeve 46and is adapted to turn or rock with the rod 48 and lift the upperspring-tension plate, so as to have the thread free to be pulled forwardwhen required. It will be perceived that when the pitman is drawn backto lift the presser-bar the arm 49 will engage the frontend of the slotin plate 50 on the pitman, and be moved therewith, and eventuate inturning the plate 51 and lift the spring-tension plate, therebyreleasing the tension on the thread and permit it to be drawn forward.WVhen the pitman moves forward, the arm 49 is free again and thespring-tension plate automatically closes down on the lower plate andrenews the tension of the thread.

On the plate 40 is laid and se- Having thus described the invention,what is claimed as new is 1. A mechanism for lifting the presser-bar ofa sewing-machine, comprising a presserbar formed with rack-teeth, abell-crank lever having teeth on the end of one arm to engage the saidrack, a pivotally-supported lever to engage the other arm of thebell-crank lever, a reciprocable pitman to operate the lever, and meansto reciprocate the pitman.

2. In a mechanism for lifting the presserbar of a sewing-machine, thecombination of a presser-bar formed with rack-teeth, a bellcrank leverhaving teeth on one arm to engage the said rack-teeth and provided witha pin in its upper end, a pivotally-supported lever 22 to engage the pinin the free arm of the bell-crank lever, a reciprocable pitman to whichthe upper end of the lever 22 is connected, a rocking lever to operatethe pitman, and a lever under the table of the machine to rock therocking lever.

3. In a mechanism for lifting the presserbar of a sewing-maohine, thecombination with a reciprocable pitman having a pawlcatch on its innerend and means connected thereto for lifting the presser-bar, ofavertical shaft, a spider-wheel mounted on the shaft, a ratchet-pinionmounted on said shaft in. the

path of the pawl-catch, and means to actuate the pitman to engage thepawl-catch with the ratchet-pinion and turn the spider-wheel to engageand hold the presser-bar elevated.

4. In a mechanism for lifting the presserbar of a sewing-machine, thecombination of thelit'ting mechanism,thepresser-barformed with a recess,a ratchet pinion, a spiderwheel turned thereby, and means to turn theratchet pinion with the spider-Wheel whereby an arm of the spider iscarried within the recess to support the presser-bar in raised position.

5. In a mechanism for raising and supporting the presser-bar of asewing-machine, the combination of the presser-bar, a rotatableratchet-pinion, a spider-wheel rotated thereby, means to lift thepresser-bar, a pitman to actuate the lifting mechanism and to rotate theratchet-pinion and bring the spider into engagement with thepresser-bar, and a lever to operate the pitman.

In testimony whereof I affix my signature in presence of two witnesses.

CONRAD TI-IEOBALD.

WVitnesses:

FRANK BRUNING, W. H. GRENE.

